Freedom of religion is a principle that supports the freedom of an individual or community, in public or private, to manifest religion or belief in teaching, practice, worship, and observance; the concept is generally recognized also to include the freedom to change religion or not to follow any religion. The freedom to leave or discontinue membership in a religion or religious group —in religious terms called "apostasy" —is also a fundamental part of religious freedom, covered by Article 18 of the Universal Declaration of Human Rights.

Freedom of religion is considered by many people and nations to be a fundamental human right.

In a country with a state religion, freedom of religion is generally considered to mean that the government permits religious practices of other sects besides the state religion, and does not persecute believers in other faiths.

Historically freedom of religion has been used to refer to the tolerance of different theological systems of belief, while freedom of worship has been defined as freedom of individual action. Each of these have existed to varying degrees. While many countries have accepted some form of religious freedom, this has also often been limited in practice through punitive taxation, repressive social legislation, and political disenfranchisement. Compare examples of individual freedom in Italy or the Muslim tradition of dhimmis, literally "protected individuals" professing an officially tolerated non-Muslim religion.

Christopher Eric Hitchens (13 April 1949 – 15 December 2011) was an English American author and journalist whose career spanned more than four decades. Hitchens, often referred to colloquially as "Hitch", was a columnist and literary critic for New Statesman, The Atlantic, The Nation, The Daily Mirror, The Times Literary Supplement and Vanity Fair. He was an author of twelve books and five collections of essays. As a staple of talk shows and lecture circuits, he was a prominent public intellectual, and his confrontational style of debate made him both a lauded and controversial figure.

Hitchens was known for his admiration of George Orwell, Thomas Paine and Thomas Jefferson, as well as for his excoriating critiques of various public figures including Mother Teresa, Bill Clinton, Henry Kissinger and Diana, Princess of Wales. Although he supported the Falklands War, his key split from the established political left began in 1989 after what he called the "tepid reaction" of the Western left to the Rushdie Affair. The September 11 attacks strengthened his internationalist embrace of an interventionist foreign policy, and his vociferous criticism of what he called "fascism with an Islamic face." His numerous editorials in support of the Iraq War caused some to label him a neoconservative, although Hitchens insisted he was not "a conservative of any kind", and his friend Ian McEwan describes him as representing the anti-totalitarian left.

Hamza Yusuf Hanson is an American Islamic scholar, and (with Zaid Shakir and Hatem Bazian) is co-founder of Zaytuna College in Berkeley, California, United States. He is a convert to Islam, and is one of the signatories of A Common Word Between Us and You, an open letter by Islamic scholars to Christian leaders, calling for peace and understanding. He has described the 9/11 attacks as "an act of 'mass murder, pure and simple'". Condemning the attacks, he has also stated "Islam was hijacked ... on that plane as an innocent victim".The Guardian newspaper in the United Kingdom reported that he "is arguably the west's most influential Islamic scholar" and added that "many Muslims find his views hard to stomach."

Hamza Yusuf was born to two academics in Washington State and raised in Northern California. In 1977, he became Muslim and subsequently traveled to the Muslim world and studied for ten years in the United Arab Emirates, Saudi Arabia, as well as North and West Africa. Hamza Yusuf spent four years studying in the United Arab Emirates and elsewhere in the Middle East. Later he traveled to West Africa and studied in Mauritania, Medina, Algeria, and Morocco under such scholars as Murabit al Haaj; Baya bin Salik, head of the Islamic court in Al-'Ain, United Arab Emirates; Muhammad Shaybani, Mufti of Abu Dhabi; Hamad al-Wali; and Muhammad al-Fatrati of Al Azhar University in Cairo, Egypt.^{[citation needed]} After more than a decade abroad, he returned to the United States and earned degrees in nursing from Imperial Valley College and religious studies at San José State University.^{[citation needed]}